The strict-dynamic CSP directive is supported in all our target browsers, and makes for a much simpler configuration. Instead of allowlisting paths, we use a per-request nonce to authorize `<script>` tags, and then those scripts are allowed to load additional scripts (or add additional inline scripts) without restriction.
This becomes especially useful when admins want to add external scripts like Google Tag Manager, or advertising scripts, which then go on to load a ton of other scripts.
All script tags introduced via themes will automatically have the nonce attribute applied, so it should be zero-effort for theme developers. Plugins *may* need some changes if they are inserting their own script tags.
This commit introduces a strict-dynamic-based CSP behind an experimental `content_security_policy_strict_dynamic` site setting.
Safari has a bug which means that scripts with the `defer` attribute are executed before stylesheets have finished loading. This is being tracked at https://bugs.webkit.org/show_bug.cgi?id=209261.
This commit works around the problem by introducing a no-op inline `<script>` to the end of our HTML document. This works because defer scripts are guaranteed to run after inline scripts, and inline scripts are guaranteed to run after any preceding stylesheets.
Technically we only need this for Safari. But given that the cost is so low, it makes sense to include it everywhere rather than incurring the complexity of gating it by user-agent.
When Discourse first introduced brotli support, reverse-proxy/CDN support for passing through the accept-encoding header to our NGINX server was very poor. Therefore, a separate `/brotli_assets/...` path was introduced to serve the brotli assets. This worked well, but introduces additional complexity and inconsistencies.
Nowadays, Brotli encoding is well supported, so we don't need the separate paths any more. Requests can be routed to the asset `.js` URLs, and NGINX will serve the brotli/gzip version of the asset automatically.
If configured, this will be used for static JS assets which are stored on S3. This can be useful if you want to use different CDN providers/configuration for Uploads and JS
This lets us use all our normal JS tooling like prettier, esline and babel on the splash screen JS. At runtime the JS file is read and inlined into the HTML. This commit also switches us to use a CSP hash rather than a nonce for the splash screen.
We previously relied on CSS animation-delay for the splash. This means that we can get inconsistent results based on device/network conditions.
This PR moves us to a more consistent timing based on {request time + 2 seconds}
Internal topic: /t/65378/65
If force_https is enabled all resource (including markdown preview and so on) will be accessed using HTTPS
If for any reason you attempt to link to non HTTPS reachable content content may appear broken
Per Google, sites are encouraged to upgrade from Universal Analytics v3 `analytics.js` to v4 `gtag.js` for Google Analytics tracking. We're giving admins the option to stay on the v3 API or migrate to v4. Admins can change the implementation they're using via the `ga_version` site setting. Eventually Google will deprecate v3, but our implementation gives admins the choice on what to use for now.
We chose this implementation to make the change less error prone, as many site admins are using custom events via the v3 UA API. With the site stetting defaulted to `v3_analytics`, site analytics won't break until the admin is ready to make the migration.
Additionally, in the v4 implementation, we do not enable automatic pageview tracking (on by default in the v4 API). Instead we rely on Discourse's page change API to report pageviews on transition to avoid double-tracking.
Per Google, sites are encouraged to upgrade from `analytics.js` to `gtag.js` for Google Analytics tracking. This commit updates core Discourse to use the new `gtag.js` API Google is asking sites to use. This API has feature parity with `analytics.js` but does not use trackers.
DEV: Replace instances of Discourse.base_uri with Discourse.base_path
This is clearer because the base_uri is actually just a path prefix. This continues the work started in 555f467.
- Define the CSP based on the requested domain / scheme (respecting force_https)
- Update EnforceHostname middleware to allow secondary domains, add specs
- Add URL scheme to anon cache key so that CSP headers are cached correctly
This allows us to use `sourceURL` which otherwise does not work. In the
future we hope to have proper source maps in development mode and
disable this again.
- Refactor source_url to avoid using eval in development
- Precompile handlebars in development
- Include template compilers when running qunit
- Remove unsafe-eval in development CSP
- Include unsafe-eval only for qunit routes in development
Plugins can add it via API if they need to use `eval`:
```
extend_content_security_policy(script_src: [:unsafe_eval])
```
See https://meta.discourse.org/t/104243
* FEATURE: allow plugins and themes to extend the default CSP
For plugins:
```
extend_content_security_policy(
script_src: ['https://domain.com/script.js', 'https://your-cdn.com/'],
style_src: ['https://domain.com/style.css']
)
```
For themes and components:
```
extend_content_security_policy:
type: list
default: "script_src:https://domain.com/|style_src:https://domain.com"
```
* clear CSP base url before each test
we have a test that stubs `Rails.env.development?` to true
* Only allow extending directives that core includes, for now
